CVE-2026-32749
Path Traversal in SiYuan Import API Enables Remote Code Execution
Publication date: 2026-03-19
Last updated on: 2026-03-23
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| b3log | siyuan | to 3.6.1 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-73 | The product allows user input to control or influence paths or file names that are used in filesystem operations. |
| CWE-22 | The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
[{'type': 'paragraph', 'content': 'CVE-2026-32749 is a path traversal vulnerability in the SiYuan personal knowledge management system versions 3.6.0 and below. The issue occurs in the import functionality where uploaded archive files are written to paths derived directly from the uploaded filename without proper sanitization. This allows an administrator to craft filenames containing path traversal sequences (like "../") to write files outside the intended temporary import directory.'}, {'type': 'paragraph', 'content': 'Because the application does not validate that the resulting file path remains within the designated import directory, attackers can overwrite arbitrary files on the server, including critical system files. This flaw enables remote code execution (RCE) especially in Docker containers running as root, leading to full container compromise.'}, {'type': 'paragraph', 'content': 'The vulnerability was fixed in version 3.6.1 by adding strict path validation to ensure that all file writes remain within the intended import directory.'}] [1, 2]
How can this vulnerability impact me? :
This vulnerability allows an administrator user to write arbitrary files to any location writable by the SiYuan process, including critical system paths.
- Overwrite workspace or application files, leading to data destruction.
- Write files to system directories such as /etc/cron.d/, enabling remote code execution (RCE) inside Docker containers running as root.
- Modify user environment files like ~/.bashrc or SSH authorized_keys, potentially allowing persistent unauthorized access.
In Docker environments running SiYuan as root (a common default), exploitation leads to full container compromise.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
[{'type': 'paragraph', 'content': 'This vulnerability can be detected by monitoring for suspicious file uploads to the SiYuan application’s import API endpoints, specifically POST /api/import/importSY and POST /api/import/importZipMd, where filenames contain path traversal sequences such as "../".'}, {'type': 'paragraph', 'content': 'Since the vulnerability involves crafted multipart filenames allowing directory traversal, detection can involve inspecting HTTP requests to these endpoints for unusual filename patterns.'}, {'type': 'paragraph', 'content': 'Example commands to detect potential exploitation attempts include using network traffic inspection tools like tcpdump or Wireshark to filter HTTP POST requests to the vulnerable endpoints and grep for "../" in multipart filename fields.'}, {'type': 'list_item', 'content': "Using tcpdump to capture HTTP POST requests to port 6806 (default SiYuan port): tcpdump -A -s 0 'tcp port 6806 and (((ip[2:2] - ((ip[0]&0xf)<<2)) - ((tcp[12]&0xf0)>>2)) != 0)' | grep -i 'POST /api/import/importSY\\|POST /api/import/importZipMd'"}, {'type': 'list_item', 'content': 'Extract and inspect multipart filenames for path traversal sequences: grep -a -oP \'filename=".*?\\.\\.\\/.*?"\' captured_http_requests.txt'}, {'type': 'paragraph', 'content': 'Additionally, checking the filesystem for unexpected files written outside the intended import directory, especially in system paths like /etc/cron.d/, ~/.bashrc, or SSH authorized_keys, can indicate exploitation.'}] [2]
What immediate steps should I take to mitigate this vulnerability?
The immediate and most effective mitigation is to upgrade the SiYuan application to version 3.6.1 or later, where this vulnerability has been fixed by enforcing strict path validation on imported files.
If upgrading is not immediately possible, restrict access to the vulnerable API endpoints to trusted administrators only, and monitor for suspicious file upload activity.
Running the SiYuan application with the least privileges possible, avoiding root or highly privileged users especially in Docker containers, can limit the impact of exploitation.
Implement network-level controls such as firewall rules to limit access to the import endpoints and consider disabling or restricting the import functionality if not needed.